摘要 |
<p>A compound of the formula : R<1>-A-D-Trp(R<2>)-Phe-R<3> wherein R<1> is hydrogen or an amino protective group, R<2> is hydrogen, an amino protective group, carbamoyl(lower)alkyl, carboxy(lower)alkyl or protected carboxy(lower)alkyl, R<3> is ar(lower)alkyl, a group of the formula: <CHEM> wherein R<4> and R<5> are each hydrogen, aryl or lower alkyl which may have suitable substituent(s), or R<4> and R<5> are linked together to form benzene-condensed lower alkylene, or a group of the formula : -OR<6> wherein R<6> is hydrogen, aryl or lower alkyl which may have suitable substituent(s), and A is a single bond or one or two amino acid(s) residue, provided that when A is one amino acid residue of -D-Trp-, then R<4> is not hydrogen, and a pharmaceutically acceptable salt thereof, processes for its preparation and pharmaceutical compositions comprising them or a pharamaceutically acceptable salt thereof in admixture with pharmaceutically acceptable carriers.</p> |